5,224 research outputs found

    The Use of Arrest Records In Pre-Employment Screening In Franklin County, Ohio

    Get PDF
    Researchers reviewed the legality of employers using arrest records without convictions in pre-employment screenings; conducted surveys and focus groups to learn about pre-employment screening practices in Franklin County, OH; and studied arrest record data to determine whether black males in the region were more likely than others to be arrested and not subsequently convicted

    Advanced subsonic transport approach noise: The relative contribution of airframe noise

    Get PDF
    With current engine technology, airframe noise is a contributing source for large commercial aircraft on approach, but not the major contributor. With the promise of much quieter jet engines with the planned new generation of high-by-pass turbofan engines, airframe noise has become a topic of interest in the advanced subsonic transport research program. The objective of this paper is to assess the contribution of airframe noise relative to the other aircraft noise sources on approach. The assessment will be made for a current technology large commercial transport aircraft and for an envisioned advanced technology aircraft. NASA's Aircraft Noise Prediction Program (ANOPP) will be used to make total aircraft noise predictions for these two aircraft types. Predicted noise levels and areas of noise contours will be used to determine the relative importance of the contributing approach noise sources. The actual set-up decks used to make the ANOPP runs for the two aircraft types are included in appendixes

    Long-range vertical propagation

    Get PDF
    Development of the advanced turboprop has led to concerns about en route noise. Advanced turboprops generate low-frequency, periodic noise signatures at relatively high levels. As demonstrated in a flight test of NASA Lewis Research Center's Propfan Test Assessment (PTA) airplane in Alabama in October 1987, the noise of an advanced turboprop operating at cruise altitudes can be audible on the ground. The assessment of the en route noise issue is difficult due to the variability in received noise levels caused by atmospheric propagation and the uncertainty in predicting community response to the relatively low-level en route noise, as compared to noise associated with airport operations. The En Route Noise Test was designed to address the atmospheric propagation of advanced turboprop noise from cruise altitudes and consisted of measuring the noise of an advance turboprop at cruise in close proximity to the turboprop and on the ground. Measured and predicted ground noise levels are presented

    PTA en route noise measurements

    Get PDF
    A long-range advanced turboprop en route noise database was obtained with weather, tracking, and onboard measurements. In-flight noise directivity measurements were made. Data repeatability within a test day was excellent. Day-to-day variability existed and is not completely understood and therefore not predicted. Comparison of a two-dimensional ray-tracing propagation model with the ensemble average ground-measured data was good; however, as stated above, the day-to-day data variability was not completely predicted. Future research will include looking at alternative propagation models. Three-dimensional ray tracing, fast field program, and the parabolic equation are possibilities. The effect of turbulence needs to be accessed

    Function and misfunction of the two promoters of the Drosophila Antennapedia gene

    Get PDF
    Journal ArticleIn the Antennapedia (Antp) gene of Drosophila melanogaster, structurally distinct RNAs arise from different transcription initiation sites. When the two sites are separated by a chromosome inversion, transcripts are produced from each fragment of the split Antp locus, and these RNAs initiate at the same nucleotide as in wild-type animals. Thus, the initiation sites are regulated by independent promoters

    Image guidance for brain metastases resection

    Get PDF
    Journal ArticleThe primary goal in removing a metastatic brain tumor is to maximize surgical resection while minimizing the risk of neurological injury. Intraoperative image guidance is frequently used in the resection of both primary and metastatic brain tumors. Stereotactic volumetric techniques allow for smaller craniotomies, facilitate lesion localization, and help neurosurgeons avoid eloquent structures. In turn, this leads to decreased patient morbidity and shorter hospitalizations. Image guidance is not without shortcomings, however, perhaps the most significant of which is inaccuracy of tumor resection associated with intraoperative brain shifts. The goal of this review is to expound on the uses of image guidance and discuss avoidance of technical pitfalls in the resection of cerebral metastatic lesions

    Primate spatial strategies and cognition: Introduction to this special issue

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106890/1/ajp22257.pd
    • …
    corecore